Flavius Claudius Constantinus

Flavius Claudius Constantinus (356-411), also known as Constantine III, was a Roman general who usurped the Western Roman Empire in Roman Britain from 407 to 409 before serving as co-emperor with Honorius from 409 to 411, succeeding Gratian and preceding Honorius.

Biography
Flavius Claudius Constantinus was born in 356 to a Roman Latin Christian family, and he became the commander of Legio VI Victrix in Roman Britain. In 406, the Western Roman Emperor Honorius recalled Legio VI from Britain to defend interests closer to Rome. Rather than abandon the British provinces, the legionaries declared for their general, Flavius Claudius Constantinus, as Emperor. Constantinus had to look to the defense of the isle against an onslaught of foes while trying to establish his dynasty, with the ultimate goal of marching on Rome and seizing pwoer as the new Western Roman Emperor. When he landed in Gaul, the Romans of Gaul and Hispania declared for him. He won several confrontations against the Vandals and quickly secured the Rhine, and Honorius sent his general Stilicho to expel Constantine. Honorius' general Sarus the Goth defeated Constantinus' generals Iustinianus and Nebiogastes, the latter of whom was killed. However, Sarus was forced to retreat to Italy as Constantine continued his advance, and Constantine made Arles his capital in 408. That summer, the Roman forces in Italy assembled to counterattack, but Constantine defeated Honorius' cousins in Hispania. The Western Roman loyalists mutinied at Ticinus and killed Stilicho, while Sarus soon deserted the Western Roman service. In 409, as Alaric I's Gothic army invaded a defenseless Italy, Honorius was forced to name Constantine as his co-emperor. From 409 to 412, the Vandals overran Constantine's Rhine defenses and burned and plundered their way through Gaul, and they then broke through Constantine's Pyrenees garrisons and invaded Hispania. Constantine's general Gerontius rebelled against him in Hispania and allied with the barbarians, hoping to attack Rome. At around the same time, Saxon pirates raided Britain, and the Romans of Britain and Armorica, distressed about Constantine's failure to defend him, rebelled and expelled Constantine's officials. In 411, Constantine was defeated by Gerontius at Vienne, and his son Constans II was captured and executed. At the same time, Honorius found a new general in Constantius III, who arrived at Arles and forced Gerontius to commit suicide and forced Constantine to surrender. Constantius imprisoned Constantine and had him beheaded en route to Ravenna, and his head was presented on a pole to Honorius before being displayed outside Carthage. Constantinus was the father of Ambrosius Aurelianus and Uther Pendragon, two future Romano-British leaders.